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2 years ago

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Carbon dioxide (CO2) gas within a piston–cylinder assembly undergoes a process from a state where p1 = 5 lbf/in.2 , V1 = 2.5 ft3

to a state where p2 = 20 lbf/in.2 , V2 = 0.5 ft3 . The relationship between pressure and volume during the process is given by p = 23.75 − 7.5V, where V is in ft3 and p is in lbf/in.2 . Determine the work for the process, in Btu.

1 answer:

sergeinik [125]2 years ago

7 0

Answer:

work 24.31 ft³/in²

Explanation:

The work in thermodynamic processes is given by a relationship between pressure changes and volume differences as follows:

W = - $\int\limits^{V2}_{V1} {p} \, dV$

In this exercise they give the pressure ratio P = 23.75 -7.5 V, so we can evaluate the integral between points two V1 = 2.5 ft3 and V2 = 0.5 ft3

W = - [23.75 V -7.5 V² / 2]

W = - [23.75 (0.5 -2.5) - 7.5 (0.5² - 2.5²) / 2]

W = - [-47.5 + 23.19] BTU

W = 24.31 ft3 / in2 = 24.31 BTU

Note that the work is positive since work is done on the gas to compress it.

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Answer:

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Explanation:

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A closed, rigid container holding 0.2 moles of a monatomic ideal gas is placed over a Bunsen burner and heated slowly, starting

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Answer:

a) 2250 J

b) 0 J

c) 2250 J

Explanation:

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the change in internal energy

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Here, n = 0.2 moles

Cv = 12.5 J/mole.K

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$\frac{P_1V_1}{P_2V_2} =\frac{T_i}{T_f}\\Since, V_1=V_2 [isochoric/process]\\\Rightarrow \frac{P_{atm}}{4P_{atm}} = \frac{300}{T_f} \\\Rightarrow T_f = 1200 K$

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$\theta=90^{\circ}$ is the angle between the direction of motion of the jet and of the magnetic field

Substituting,

$F=(0.5\cdot 10^{-6})(660)(8.0\cdot 10^{-5})=2.64\cdot 10^{-8} N$

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- force: thumb --> north

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As we can see from part (a), the magnitude of the force is not really big, so the effects are negligible.

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Answer:

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Part e)

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Explanation:

Part a)

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Part b)

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Part c)

angular acceleration is given as

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$\alpha = \frac{8.17 - 0}{11.9}$

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Part d)

When its angular speed changes to 120 rpm

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so we have

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Part e)

now for uniform acceleration we have

$\omega_f - \omega_i = \alpha t$

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